Camp stove with sheet metal burner



Jan. 14, 1964 H. HOENISCH 3,117,568

CAMP STOVE WITH SHEET METAL BURNER Filed March 21, 1961 5 Sheets-Sheet 1INV EN TOR.

Jan. 14, 1964 H. HOENISCH 3,117,568

CAMP STOVE WITH SHEET METAL BURNER Filed March 21, 1961 5 Sheets-Sheet 2INVENTOR. fldra/ #0 7773 6/? Jan. 14, 1964 H. HOENISCH 3,117,568

CAMP STOVE WITH SHEET METAL BURNER Filed March 21, 1961 5 Sheets-Sheet 3Jan. 14, 1964 1-1. HOENISCH CAMP STOVE WITH SHEET METAL BURNER 5Sheets-Sheet 4 Filed March 21, 1961 INVENTOR. flaro/J #00 71. .3 (/4 H.HOENISCH CAMP STOVE WITH SHEET METAL BURNER Jan. 14, 1964 5 Sheets-Sheet 5 Filed March 21, 1961 M W M J United States Patent 3,117,568 CAMPSTOVE WITH SHEET METAL BURNER Harold Hoenisch, Albert Lea, Minn.,assignor to King- Faeeley Thermos (1a., Ann Arbor, Mich, a corporationof Michigan Filed Mar. 21, 1961, Ser. No. 97,181 8 Claims. (Cl. 126-38)This invention relates to camp stoves, and more particularly to portablepressure stoves for burning gasoline and other hydrocarbon liquids.

It is an object of the invention to provide a novel and improved stoveof this type which is extremely inexpensive to manufacture and in whicha sheet metal burner manifold may be utilized without danger ofexcessive manifold temperatures which might detract from efficient stoveoperation.

It is another object to provide an improved stove of this nature whichincludes a novel burner ring construction creating eificient flameconfiguration with a minimum number of parts and which reduces thepossibility of burner aperture clogging and further results in a lowertemperature for the manifold on which the burner is mounted.

It is also an object to provide an improved stove having the abovecharacteristics which incorporates means permitting the stove to beeificiently used at high altitudes where the combustion air requirementsare great, at the same time providing for operation at lower altitudesby a simple adjustment.

Other objects, features, and advantages of the present invention willbecome apparent from the subsequent description, taken in conjuncitonwith the accompanying drawings.

In the drawings:

FIGURE 1 is a perspective view of the stove shown in its open positionwith the gasoline tank operatively mounted on the front of the casing;

FIGURE 2 is a top view of the stove when in open and operative position,showing the relative location of various stove components;

FEGURE 3 is a side elevational view in cross section taken along theline 33 of FIGURE 2 and showing the manner in which the generator tubeis connected to the venturi inductor;

FlGURE 4 is an enlarged cross-sectional view taken along the line 4-4 ofFIGURE 3 and showing the air adjustment for the venturi inductor;

FIGURE 5 is a front elevational view, partly in cross section, of themanifold assembly showing the air control valve for the auxiliary burnerring;

FIGURE 6 is a top elevational view of the manifold assembly partly incross section and showing the burner ring construction;

FEGURE 7 is a cross-sectional view in elevation taken along the line 77of FIGURE 5 and showing the manner of joining the upper and lowersections of the manifold;

FEGURE 8 is a top plan view of the lower manifold member; and

FIGURE 9 is a cross-sectional view in elevation taken along line 9-9 ofFIGURE 6 and showing the manner in which the burner rings are secured tothe upper manifold plate.

in general terms, the illustrated embodiment of the invention comprisesa casing with a hinged upper lid and a gasoline tank mountable on thecasing front with a generator-filter tube which projects into a venturiinductor. The latter in turn is connected to a burner manifold ofelongated shape secured Within the casing, the manifold being fabricatedof stamped sheet metal parts sealed together. Burner rings of invertedcup shape are mounted 3d N558 Patented Jan. 14, 1964 ice on themanifold, each burner ring having an annular depressed portion adjacentat the outer edge with radially extending slots having inner portionsformed in the main horizontal burner ring section and an outer inclinedsection adjacent the depressed portion. A raised burner ring portionsurrounds the depressed portion.

It has been found that the novel burner configuration of this inventionreduces clogging, prevents excessive manifold temperature, and permitsmanufacturer of the burner with a minimum number of parts.

Another feature of the invention is the provision of a venturi inductorat the generator-filter tube outlet, together with an adjustable airinlet for the inductor which is of large size, so that the stove may beused at high altitudes as well as near sea level.

Referring more particularly to the drawings, the stove is generallyindicated at 11 and comprises a casing generally indicated at 12 with alower portion 13 and an upper lid 14 hinged thereto at 15. The casing isof generally rectangular shape, and a grill 16 for supporting utensilsis provided above the casing, this grill being swingable between a lowerposition as seen in FIGURE 1 and an upper position about hinges 15. Airdeflector shields 17 are foldably mounted on the side edges of the grilland may be collapsed when the stove is being transported.

A subassembly generally indicated at 18 and comprising a gasoline tank19, a valve body 21 and a generatorfilter tube 22 of known construction,is provided, this subassembly being mountable on the front of casing 13by means of hooks 23 and beign storable within the casing when the stoveis being transported. Tank 1% has a filler plug 24 and a pressure pump25, while valve body 21 is provided with an air valve controlled byhandle 26 and a fuel-flow control valve having a handle 27. When thetank is mounted on the front of the casing, generatorfilter tube 22exends through and beneath grill 16 into the entrance of a venturiinductor tube 28, as seen in FIGURE 3.

Tube 28 is of generally U-shaped configuration, with an upper entranceof relatively wide circular shape which tapers down to a narrow mainportion. An air inductor shield 29 is mounted on the entrance portion oftube 28 and extends rearwardly therefrom, as seen in FIGURE 3. Thisshield is of elongated inverted channel shape with a front wall 31having an aperture into which the exit end of tube 22 extends. Theunderside of the entrance portion of tube 28 has an elongated air inlet32, and a shutter 33 shaped as an incomplete ring is mounted within thetube entrance as seen in FiGURE 4. Shutter 33 is rotatable betweenpositions opening or partially closing air inlet 32., and for thispurpose a screw 34 is mounted on the shutter and extends upwardlythrough access slots in members 28 and 29.

The lower end of inductor tube 28 is secured to a burner manifoldassembly generally indicated at 35. The construction of this manifoldassembly is perhaps best seen in FIGURES 5 through 9. The manifoldassembly comprises a lower manifold member 36 and an upper manifoldmember 37, these members being of generally elongated shape andpreferably being stamped of sheet metal and sealed together around theiredges by overlapping flanges 38 and 39 on members as and 37respectively. Legs 41, which may likewise be fabricated of bent sheetmetal, serve to support the manifold assembly above the bottom of casing12 as seen in FIGURE 5.

The lower manifold member 36 has an outer flat portion and an elongatedcentral depressed portion 42, as seen in FIGURE 8. The left hand section43 of depression 42 as seen in this figure, is somewhat enlarged, andits rear wall 44 has an apertured portion 45 within which the lower endof inductor tube 23 is secured. An apertured portion re is provided inthe bottom of the ri ht hand portion of depression 42, as seen in FIGURE8, this apertured portion receiving an internally threaded bushing 47seen in FIGURE 9 for purposes which will hereafter appear.

Upper plate 37 of manifold assembly 35 is of generally fiat shape, withcentral portions thereof having slightly raised ribs 48 forstrengthening purposes. The left and right hand portions of plate 37, asseen in FIGURE 6, have annular raised portions 4% and 51 respectively,these raised portions being shown as having: the same diameter. A pairof threaded bolt receiving members 52 are secured beneath plate 37inwardly of each raised portion 49 and 51 in order to accommodate boltswhich hold down the burner rings to be later described. A plurality offuelilow apertures 53 are provided in the central portion of the platearea within raised portion 49, as seen in FIG- URE 6. A singlerelatively large fuel-flow aperture 54 is provided in the por.ion ofplate 37 within raised portion 51, aperture 54 being concentric withthis raised portion.

A pair of burner rings generally indicated at 55 and a: are mounted onraised portions 49 and 51. respectively of plate 37, each of theseburner rings being of identical construction and preferably fabricatedof stamped and drawn sheet metal. Each burner ring is of generallyinverted cup shape, with a cylindrical outer wall 57 adapted to fitimmediately outside of raised portion 49 or 51. The upper portion ofwall 57 is inwardly and downwardly curved so as to form an annular outerwall designated at 58. The lower portion of this outer wall is againreversely bent as indicated at 59, and is thereafter inclined upwardlyand inwardly as indicated at 63. The central portion of each burnerring, indicated at 62, is relatively flat but is of a lower height thanthe top of Wall 58. Slightly raised stifienirig ribs 63 may be formed inthis central flat portion, together with apertured portions forreceiving bolts 64 which are threadable into members 52 for securing theburner rings in place.

A large number of circumferentially spaced and radially extending iiameslots 65 are formed in each burner ring. These slots begin at a pointsomewhat inwardly of inclined portion 61, and extend through thisinclined portion to the lowermost portion of depression 5%. Each slotthus has an inner horizontal portion and an outer inclined portion, thelatter portion facing wall 58 which is in spaced relation therewith. Afuel control disc valve 66 is provided beneath circular aperture 54,this valve being mounted at the upper end of a threaded post 67 mountedin bushing 47. The lower end of post 67 carries a lever 63 securedthereto, this lever being roekable by a handle 69 which is pivotedthereto and extends forwardly therefrom to the front end of the casingas seen in FIG- URE 1. Rotation of lever 68 will cause post 67 to beraised or lowered, thereby shutting off or adjusting the amount offuel-air mixture which may flow upwardly through aperture 54 toauxiliary burner 56.

in operation, pressurizing tank 19 and opening both the air and fuelflow valves will permit fuel-air mixture to flow through tubes 22 and 28into the manifold and rent the manifold into the burner rings, where itmay be ignited. After a short period of operation of main burner 55,tube 22 will be heated sufficiently to vaporize the liquid gasoline inthe generator. This makes it feasible to permit air valve 2: to beclosed, secondary air induced at venturi tube 28 being sufiicient tosupport com bustion. The amount of air flowing into the venturi tube maybe adjusted by shutter 33.

Fuel flowing outwardly through slots 65 will burn in a manner such thatclogging of the slots will be substantially reduced. Annular wall 58will serve to prevent induction of air flow into the slots which mightdetract from air control and result in unstable burning. Theconstruction is also such that very little heat will be carried back tothe manifold itself, and the sheet metal manifold construction,fabrigata'ole at exceedingly low cost as compared with conventional castversions, will thus still serve in a completely satisfactory manner.

While it will be apparent that the preferred embodiment of the inventiondisclosed is well calculated to ful fill the objects above stated, itwill be appreciated that the V invention is susceptible to modification,variation and change without departing from the proper scope or fairmeaning of the subjoined claims.

What is claimed is:

1. In a hydrocarbon-burning stove of the type having a fuel tank, agenerator-filter tube leading from said tank, an inductor tube connectedto the exit end of said generator-filter tube, a manifold connected tothe exit end of said inductor tube, and a burner ring mounted on saidmanifold, said burner ring being of generally inverted cup-shapedconfiguration, the improvement comprising an annular depression adjacentthe upper outer edge of said burner ring, and a plurality of slots insaid burner ring extending radially inwardly a short distance from saiddepression, the inner wall of said depression being inclined upwardlyand inwardly, the outer portions of said slots being formed in saidinclined wall.

2. The combination according to claim 1, the top of the outer wall ofsaid depression being higher than the portion of said burner ringinwardly of said depression.

3. The combination according to claim 1, said manifold comprising aplurality of sheet metal stampings sealed together, the lower edge ofsaid burner ring being engageable with one of said stampings.

4. In a hydrocarbon-burning stove, a manifold comprising upper and lowersheet metal stampings sealed together along their edges, said lowerstamping having a central depressed portion forming a chamber, the upperstamping being relatively flat, a burner ring having an annularsubstantially vertical side wall and a generally flat circular top,means securing said burner ring to said flat manifold stamping with thelower edge of said side wall engaging said stamping, apertured portionsin said fiat manifold stamping beneath said burner ring for fuel flow,an annular depressed portion immediately inwardly of the juncture ofsaid burner ring side wall and top, and a plurality of circumferentiallyspaced radially extending flame slots in said burner ring extending ashort distance inwardly from said annular depressed portion, the innerwall of said depressed portion being inclined upwardly and inwardly, theouter portions of said slots being formed in said inclined wall.

5. In a hydrocarbon-burning stove, a manifold having a flat top, aburner ring of generally inverted cup shape secured to said flat top,said burner ring having a substantially vertical annular side wall thelower edge of which engages said manifold top, an annular depressedportion in said burner ring immediately inwardly of the upper edge ofsaid side wall, said depression having an upwardly and inwardly inclinedinner wall and a substantially vertical outer wall of greater heightthan said inner wall, and a plurality of circumferentially spaced flameslots in said burner ring extending a short distance inwardly from saiddepressed portion.

6. In an integral burner ring construction for a hydrocarbon-burningstove, an annular upwardly extending sidewall having an exposeddownwardly facing lower edge, a reversely and downwardly bent annularportion integrally formed with the top of said side wall, a secondreversely' and upwardly bent annular portion integrally formed with: thebottom of said downwardly bent portion and a substantial distance abovethe lower edge of said side Wall, a substantially flat circular portionintegrally formed with and extending inwardly from the upper end of saidsecond reversely bent portion, and a plurality of circumferentiallyspaced slots in said circular portion extending a short distanceinwardly from the depression formed by said second reversely bentportion.

7. In an integral burner ring construction for a hydro-- carbon-burningstove, an annular upwardly extending side wall having an exposeddownwardly facing lower edge, a reversely and downwardly bent annularportion integrally formed with the top of said side wall, a secondreversely and upwardly bent annular portion integrally formed with thebottom of said downwardly bent portion and a substantial distance abovethe lower edge of said side wall, a substantially fiat circular portionintegrally formed with and extending inwardly from the upper end of saidsecond reversely bent portion, and a plurality of circumferentiallyspaced slots in said circular portion extending a short distanceinwardly from the depression formed by said second reversely bentportion, the inner wall of said second reversely bent portion beinginclined upwardly and inwardly, the outer portions of said slots beingformed in said inclined inner wall.

8. In a portable hydrocarbon-burning stove of the type having a casing,a burner manifold within said casing, a fuel tank detachably mountableon said casing, and a generator-filter tube extending inwardly from saidfuel tank over said burner manifold, the combination with said stove ofa venturi inductor tube having a relatively wide horizontal entranceportion. and a narrow portion leading therefrom to said burner manifold,an air inductor shield of elongated inverted channel shape having afront wall with an apertured portion into which the exit end of saidgenerator-filter tube extends, an elongated air inlet on the undersideof said entrance portion of the venturi inductor tube, a shutter shapedas an incomplete ring mounted within said entrance portion and inrotatable sliding relation therewith between positions opening orpartially closing said air inlet, access slots in registry on saidentrance portion and shield, and a screw mounted on said shutter andextending through said access slots.

References Cited in the file of this patent UNITED STATES PATENTS390,352 Doty Oct. 2, 1888 401,783 Kahn Apr. 23, 1889 427,666 Bucklin May13, 1890 761,098 Porter May 31, 1904 1,005,431 Huber Oct. 10, 19111,551,788 Benson Sept. 1, 1925 2,302,880 Nelson et al. Nov. 24, 19422,499,556 Zink Mar. 7, 1950 2,638,976 Vixler May 19, 1953 2,711,215Squire et al. June 21, 1955 2,744,809 Falligant May 8, 1956 2,815,070Lamar Dec. 3, 1957 2,824,605 Dolby Feb. 25, 1958

1. IN A HYDROCARBON-BURNING STOVE OF THE TYPE HAVING A FUEL TANK, AGENERATOR-FILTER TUBE LEADING FROM SAID TANK, AN INDUCTOR TUBE CONNECTEDTO THE EXIT END OF SAID GENERATOR-FILTER TUBE, A MANIFOLD CONNECTED TOTHE EXIT END OF SAID INDUCTOR TUBE, AND A BURNER RING MOUNTED ON SAIDMANIFOLD, SAID BURNER RING BEING OF GENERALLY INVERTED CUP-SHAPEDCONFIGURATION, THE IMPROVEMENT COMPRISING AN ANNULAR DEPRESSION ADJACENTTHE UPPER OUTER EDGE OF SAID BURNER RING, AND A PLURALITY OF SLOTS INSAID BURNER RING EXTENDING RADIALLY INWARDLY A SHORT DISTANCE FROM SAIDDEPRESSION, THE INNER WALL OF SAID DEPRESSION BEING INCLINED UPWARDLYAND INWARDLY, THE OUTER PORTIONS OF SAID SLOTS BEING FORMED IN SAIDINCLINED WALL.